/Engine/Source/Runtime/Core/Public/Misc/CString.h
Finds string in string, case insensitive
Position in Str if Find was found, otherwise, nullptr. If FindLen is 0, returns Str.
static const [CharType](API\Runtime\Core\Misc\TCString\CharType) * Strnistr ( const [CharType](API\Runtime\Core\Misc\TCString\CharType) * Str, int32 InStrLen, const [CharType](API\Runtime\Core\Misc\TCString\CharType) * Find, int32 FindLen )